Improvement in mainspring adjustments for watches



JQHN S. "Emis ma HENRY BJAMES iMPROvED MAxNSPRxNCl ADQUSTMNT.

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UNrrnD T Arns A'rnn JOHN S. TAXS AND HENRY JAMES, OE TRENTON, NEV JERSEY, ASSIGN- ORS TO HENRY B. JAMES.

IMPROVEMENT IN MAINSPRING ABJUSTVIENTS FCR WATCHES.

Specification forming part of Letters Patent No. 122,414, dated January 2, 1872 antedated December 2l, 1871.

SPECIFICATION.

We, JOHN S. Taxis and HENRY B. JAMES, of Trenton, in the county ot' Mercer and State ot' New Jersey, have invented certain Improvements for the Adjustment ot' Mainsprings in Time-Keepers and other movements, ot' which.

the following is a specification:

Description of the Accmnptmyiag Drawings.

Figure 1 is a watch-barrel and mainsgring, enlarged, illustrating the invention on a going barrel. Fig. 2 illustrates the invention as applicable to a stationary barrel, and to the time and striking movements of -aclock.

The first part ot' our invention consists in connecting the outer end of the niainspring, by means ot' a link, to a stud on the tace oi" its barrel between the center and periphery oi" the saine, t'or the purpose of reducing the leverage, and consequently the power ot' the spring upon the barrel during the tirst two turns in nnwinding, before its outer spire comes in i'rictioirti ght contact with the rim ofthe barrel. Hhe second `part ot' our invention consists in the application and arrangement oi stops on the link or shifting-arm and on the arbor, for the purpose or' preventing the overwindingot' the mainsprin g.

To enable those skilled in the art to make and use our invention, we will proceed to describe its construction and operation.

A in l represents the shifting-arm or link, which is made ot' tempered steel, by prei'- erence, and arranged in arecess formed in the barrellicad or whe-el B, so as not to projectl other end, marked b, being` bent down to extend through a slot in the barrel, is attached to the outer end of the mainspring C, hookfashion, in the usualmanner. The outer end oi' the mainspring is firmly secured to the arbor D. The spring, attached as above described, acts on the barrel through the link only during, say, the lirst two turns in uncoiling, by which time its outer spire has braced itself friction-tight against the rim ot' the barrel, so that it will, during the last turns, act by friction directly on such rim. Thus a differential leverage ot' the spring is obtained, whereby the power it exerts on the barrel is approximately eqnalized suli'icient for all practical purposes. A stop, e, is on the arbor l), to act against a stop, d, on the lever when drawn to it by the spring in winding. It' desirable an eXtra arm and stop may be arranged on the opposite side of the swivel and screw a, to act in a similar manner in unwinding; 0r the usual stop-work may be used in combination with the lever adjustment, as described, it' preterable. Two levers may be combined to act on opposite sides of the spring, it' desired. rne lever may act as described it' connected with a spring and secured to the wheel or frame, as shown in Fi 2. e is the spring. f is a socket to secure it and the leverA to the frame E 5 or the levers and mainsprings C C may be attached and operated in the same manner as in l.

l ani aware that a patent was granted to Arthur lV-adsworth on the 5th day otn J une, A. D. 1869, in which he describes and claims a mode ot' attaching the outer end ot' the spring to a pivoted segment of the rim ot its barrel. rlhis invention is distinguished from that just alludedto in the arrangement ot' the link and the location of its pivotal point, which are such as to ett'ect the approximate equalization ot' the spring power, in the manner set forth; whereas, no such result is or can be produced by attaching the spring to a link, disposed as Vsaid /Vadsworthls is, to any greater extent than where the spring is hooked directly to the rim oi' the barrel.

AA, which is secured at a point within the cir- Y 2 i Y d 122,414

cie of the spring, substantially as described, scribed, for the purpose of preventing over- Whereby the spring power is reduced and equal- Winding. ized, substantially as specified.

2. The combina-tion of the stop c, attached to Jehe Winding-arbor of a Watch movement, Witnesses present:

SAMUEL CARPENTER, GEORGE W. GATES. (36) JOHN S. TAXIS. HENRY B. JAMES.

with :L stop, d, on the shifting-arm A attached to the barrel, arranged substantially -as de- 

